Democrats need more than just opposition to President Donald Trump to gain congressional seats in November's elections, Senate Minority Leader Chuck Schumer said Monday.

The New York Democrat said he understands midterms often serve as a referendum on the president, and Trump has endured low approval ratings since he took office. But Schumer believes Democrats need a strong economic message, as well, if they are going to win a majority in the House or Senate.

"You cannot just run against Donald Trump," Schumer said, speaking next to Senate Majority Leader Mitch McConnell at an event at the University of Louisville. "And it is the job of we Democrats to put together a strong, cohesive, economic group of proposals aimed at the middle class and those struggling to get there."

Democrats need to promote policies like cutting the costs of student loans, increasing access to rural broadband and boosting the availability of child care, he argued. Schumer added that his party needs to "focus like a laser" on economic issues.

The two major parties will pit differing economic arguments against one another in the bitter battle for control of Congress in November. On the GOP side, lawmakers plan to pitch a strong U.S. economy and the effects of the recently passed Republican tax law.

Democrats see opportunity in the House, where they plan to target 101 seats held by the GOP, according to NBC News. That figure goes well beyond districts won by Hillary Clinton in the 2016 presidential election.

Republicans hold a 238 to 193 seat majority in the House, with four current vacancies. That means Democrats need to pick up 25 GOP seats to take over the House. According to NBC News' count, at least 20 Republican incumbents have said they will retire this year.

Republicans hold a one-seat edge in the Senate, but they have a much better chance of keeping control of that chamber. Democrats hold 26 of the 34 Senate seats on 2018 ballots. Several Democrats face tough re-election bids in states Trump won in 2016 like Missouri, North Dakota, West Virginia, Pennsylvania, Ohio, Wisconsin, Michigan and Florida.